1. Field of the Invention
The present invention relates to a semiconductor light emitting device and a method of manufacturing the same.
2. Description of the Related Art
A light emitting diode (LED) is one type of semiconductor light emitting device. In an LED, energy is released in the form of light due to electron-hole recombination in a p-n junction structure. That is, when a forward voltage is applied to a semiconductor of a specific element, electrons recombine with electron holes through a p-n junction, and an energy level therein becomes lower than in the case in which electrons and holes are separated. By this energy difference, an LED emits light to the outside.
At this time, the light is generated from an active layer, passes through an individual stack constituting a light emitting device, and is finally radiated to the outside. Meanwhile, an air layer forming the outer atmosphere of the light emitting device is a low refractive index layer having a refractive index of approximately 1, while the outermost layer of the light emitting device has a relatively high refractive index. Normally, when light is made incident onto a layer having a lower refractive index from a layer having a higher refractive index, the incident light is not entirely radiated but partially reflected, thereby impairing the light extraction efficiency of the light emitting device. Thus, a portion of light emitted from a light emitting region may be trapped within a light emitting structure without being radiated to the outside, thereby undermining light extraction efficiency. To address this issue in the related art, there has been an attempt to induce a change in a light path by forming an uneven structure in the outer part of a light emitting structure or the surface of a substrate.